<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title></title>
</head>
<body>
<div style="height: 200px;width: 100%;">
    <div style="height: 100%;background: red;width: 200px;">
        <div id="aaaa" style="height:50% ;background: yellow;width: 200px;"></div>
        <div style="height: 50%;background-color: blue;width: 200px;"></div>
    </div>
</div>
</body>
</html>
